A liquid crystal display device and the like are known as display devices. Liquid crystal display devices, having features such as lightness, slimness and low power consumption, have been used in various fields as office automation (OA) devices such as personal computers and display devices such as television sets. Recently, the liquid crystal display devices are also used as mobile terminal devices such as mobile telephones and display devices such as car navigation devices and game consoles. In recent years, a configuration of assigning a touch sensing function to a liquid crystal display panel which displays images is disclosed.